The Docker file on the hub is updated after the build starts. In addition, the expected build means that it is not already running. Sometimes it takes some time. Do you have a github account Associated in the Settings section of the Docker repository? You can go to the status page to see that something is not working here: https://status.docker.com/ .
By the way, I have several projects on the Docker hub, I went to one of them just now and clicked "Build" (this is not necessary if your github is connected, it does automatic assembly), and it got stuck in waiting. Sometimes it takes a lot of time.
3 Docker , . , :-( Docker.